diff --git a/seed/applicationservice/2022.03.08/oauth2-client/funcs/oauth2_client.py b/seed/applicationservice/2022.03.08/oauth2-client/funcs/oauth2_client.py
new file mode 100644
index 0000000..7181e84
--- /dev/null
+++ b/seed/applicationservice/2022.03.08/oauth2-client/funcs/oauth2_client.py
@@ -0,0 +1,4 @@
+def calc_oauth2_client_external(external, location, *extras):
+    if not external or not location or None in extras:
+        return
+    return f'https://{external}{location[0]}' + ''.join(extras)